From the Guidelines
Management of moderate (50-69%) internal carotid artery (ICA) stenosis primarily involves aggressive medical therapy rather than surgical intervention, as recommended by the 2024 ESC guidelines for the management of peripheral arterial and aortic diseases 1. The cornerstone of treatment includes:
- Antiplatelet therapy with aspirin (75-325 mg daily) or clopidogrel (75 mg daily) if aspirin intolerant
- High-intensity statin therapy, typically atorvastatin 40-80 mg or rosuvastatin 20-40 mg daily, aiming for LDL levels below 70 mg/dL
- Blood pressure control to less than 140/90 mmHg (or lower in diabetic patients) using appropriate antihypertensives
- Diabetes management targeting HbA1c below 7% is important for affected patients
- Lifestyle modifications are crucial, including smoking cessation, regular physical activity, weight management, and a Mediterranean or DASH diet Regular follow-up with carotid ultrasound every 6-12 months is recommended to monitor for disease progression. Carotid revascularization (endarterectomy or stenting) is generally not recommended for this degree of stenosis unless the patient experiences recurrent symptoms despite optimal medical therapy or shows rapid progression, as stated in the 2024 ESC guidelines 1. This approach is based on evidence showing that the risk of stroke in patients with moderate asymptomatic stenosis is relatively low (approximately 1-2% annually) when managed with contemporary medical therapy, making the risk-benefit ratio unfavorable for invasive procedures in most cases. Key considerations for carotid revascularization include:
- A documented 30-day risk of procedural death/stroke of <6% 1
- Patient-specific factors, such as age, sex, and comorbidities 1
- The expertise of the surgeon or interventionist and the center's performance results 1
From the Research
Management of 50-69% iCA Stenosis
- The management of asymptomatic internal carotid artery (iCA) stenosis is a topic of ongoing research, with studies comparing the efficacy of surgical and medical management options 2, 3, 4.
- For patients with 50-69% iCA stenosis, the risk of stroke is lower compared to those with more severe stenosis, and medical management alone may be sufficient 2.
- However, some studies suggest that carotid endarterectomy (CEA) or carotid artery stenting (CAS) may be beneficial for patients with asymptomatic iCA stenosis, even at lower levels of stenosis 3, 4.
- A study published in 2023 found that the risk of new cerebral ischemic events in patients with symptomatic iCA stenosis while awaiting CAS placement was 2.5 per 1000 patient days of observation, with 6.9% of patients experiencing new events 5.
Comparison of CEA and CAS
- Studies have compared the outcomes of CEA and CAS for asymptomatic iCA stenosis, with some finding similar results in terms of stroke risk and mortality 3, 4.
- A systematic review and meta-analysis found that CAS was associated with a decreased risk of myocardial infarction (MI) compared to CEA, but a slightly increased risk of stroke 4.
- Another study found that CEA was associated with a decreased risk of perioperative stroke and increased risk of MI, but no difference in mortality compared to CAS 4.
Risk Factors for Progression
- A study published in 1996 found that clinical risk factors such as elevated systolic blood pressure and decreased ankle-brachial index were associated with progression from <60% to ≥60% asymptomatic iCA stenosis 6.
- The same study found that the initial peak systolic velocity (PSV) on duplex scan was a predictor of progression, with higher velocities associated with a greater risk of progression 6.